Peach and nectarine processing by-products as substrate for growing mushrooms

Large amounts of peach and nectarine by-products generated by fruit processing companies are currently a waste product and their disposal has become a constraint for expanding the industry. Growing mushrooms, especially those capable of utilizing cellulose and lignin from these underutilized resources, can be profitable. Therefore, the objective of the present study was to grow pink oyster and shiitake mushrooms on nectarine pomace and peach pits, respectively. Pink oyster mushrooms were grown on a mixture of nectarine pomace and straw in 80:20 ratio with calcium carbonate and ammonium sulfate. Ground peach pits with various ratios of sawdust, woodchips, and wheat bran were evaluated as substrate for growing shiitake. Pink oyster mushroom bags often developed contamination problems with Trichoderma spp. possibly due to presence of dry pockets in the substrate during autoclaving. Shiitake mycelium colonized in the substrate but growth conditions did not stimulate transition from vegetative to reproductive growth.